package com.zhang.security.filter;

import com.zhang.security.security.TokenManager;
import org.apache.tomcat.util.modeler.BaseAttributeFilter;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.web.authentication.www.BasicAuthenticationFilter;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

/**
 * @author ZhangJZ
 * @create 2022-05-13 21:27
 */
public class TokenAuthFilter extends BasicAuthenticationFilter {
    private TokenManager tokenManager;
    private RedisTemplate redisTemplate;

    public TokenAuthFilter(AuthenticationManager authenticationManager, TokenManager tokenManager, RedisTemplate redisTemplate) {
        super(authenticationManager);
        this.tokenManager = tokenManager;
        this.redisTemplate = redisTemplate;
    }

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain chain) throws IOException, ServletException {
        //获取当前认证成功用户权限信息

        UsernamePasswordAuthenticationToken authRequest = getAUthentication(request);

        //如果有这个权限的信息,就放到权限上下文中
        if (authRequest != null) {
            SecurityContextHolder.getContext().setAuthentication(authRequest);
        }
        chain.doFilter(request,response);


    }

    private UsernamePasswordAuthenticationToken getAUthentication(HttpServletRequest request) {
        String token = request.getHeader("token");
        if (token != null) {
            //从token中获取用户名
            String username = tokenManager.getUserInfoFromToken(token);
            List<String> permissionValueList = (List<String>) redisTemplate.opsForValue().get(username);
            Collection<GrantedAuthority> authorities = new ArrayList<>();
            for (String s : permissionValueList) {
                SimpleGrantedAuthority auth = new SimpleGrantedAuthority(s);
                authorities.add(auth);
            }
            return new UsernamePasswordAuthenticationToken(username, token, authorities);
        }

        return null;

    }
}
